I have no idea where I got this from but I think it was Bill Gillespie.
If you like it and it helps, we will say it was from him. If it sucks than I got it from someone else because Bill is one of the best Strength and Conditioning Coaches I've ever meet (as well as a hell of a lifter)
One of the best statements he ever said to me and this dates back into the mid 90's was...
"Since when did Squatting and Deadlifting not become functional?" - Bill Gillespie
FIRST - SEE A DOCTOR TO FIND OUT WHAT THE PROBLEM IS.
This is what I did when my shoulder was acting up and I am happy I found this as I am going to start using it again.
Start with the cuff complex which is listed below.
Use a 5 pound plate for all the movements.
Start with one set of 10 reps with 5 pounds and work up to 2 sets of 20 with 20 pounds over time (by this I mean months, not by next week).
Overhead press
Overhead triceps extension
Side raises with thumbs up
Side raises with thumbs middle
Front raise with thumbs up
Front raise with thumbs middle
Bent side raise thumbs up
Bent side raise thumbs middle
Bent front raise thumbs up
Bent front raise thumbs middle
Zottsman curl – this is like a curl with an extra twist at the top.
External rotation – only top half
External rotation – only bottom half
When finished with this workout, start the following shoulder traction work.
Lay on bench with a average or light band set up like you would a reverse band press. Lay on the bench and strap the band around your wrist (don’t grab the band, you want all the stretch to go to the shoulder and not be limited by your grip strength). Let the band pull your arm up and out. Move the arm around to try and lengthen the shoulder joint.
Do the same as above with the band wrapped around the power rack in different locations, except now you will be standing in front of the rack with the band on the side post of the rack. Move and stretch in every direction you can think of.
Do the traction work before and after all training sessions. Do the cuff work 4 – 5 times the first week, 3 times the second week and then only on upper body days after that.